Contact device with an opto-electric converter and fixable at a structural element in a building

ABSTRACT

The invention concerns a contact device that comprises a carrier member ( 10 ), a receiving unit ( 12 ) for receiving at least one optical fibre ( 14 ), a control circuit ( 16 ) that includes a converter for converting optical signals to electrical signals and vice versa and a first contact member ( 18 ) connected to the control circuit ( 16 ) and designed such that a second contact member may be connected to the first contact member ( 18 ) for conducting electrical signals from and to the first contact member ( 18 ). The receiving unit ( 12 ), the control circuit ( 16 ) and the first contact member ( 18 ) are fixed relative to the carrier member ( 10 ). The contact device is designed to be fixable at a structural element ( 20 ) in a room ( 22 ) or other part ( 22 ) of a building. The invention also concerns a use of the contact device.

BACKGROUND OF THE INVENTION AND PRIOR ART

The present invention concerns a contact device, more precisely acontact device to which at least one optical fibre is led. The inventionalso concerns the use of such a contact device.

GB-A-2 178 919 shows a system with a network for distributing wide bandsignals via optical fibres. The network is particularly suited totransmit digital video signals to TV-apparatuses. The signals are ledvia optical fibres to a receiver/transmitter unit positioned in aTV-receiver. The signals are thus led in an optical manner all the wayto the TV-apparatus.

U.S. Pat. No. 4,555,810 describes a device for the distribution ofoptical signals. The optical signals are led to optical wall contacts.Thereafter a conversion of the optical signals from the optical wallcontacts takes place. The converter may either form a part of anapparatus, for example a TV-apparatus, or may form a part of a separateunit that is plugged into the wall contact.

EP-A-7 537 774 describes a wall socket with both electrical conductorsfor supply voltage and optical fibres. The wall socket is primarilyintended for the purpose that the apparatus that is supplied with thesupply voltage from the socket should also be able to communicate withthe help of optical signals. The wall socket also comprises one or moreoptoelectric converters. The wall socket comprises an optical contactmember that may co-operate with a corresponding optical plug. The wallsocket is primarily intended to receive optical signals from anapparatus in the room and to convert these signals to electrical signalsand vice versa, i.e. to convert electrical signals to optical signalsand to transmit these optical signals to an apparatus in the room.

The systems that are described in the first two documents above have thedisadvantage that it is necessary to arrange optoelectric convertersoutside of the contact device itself, either in the apparatus to whichthe optical signals are led or in a separate converter that is pluggedinto a wall socket.

An optical contact of the kind that is described in the last describeddocument above has several disadvantages. Such an optical contactrequires a relatively complicated plug with which the contactco-operates, since otherwise losses in the optical transmission betweenthe wall socket and the plug may easily occur. Furthermore, mostapparatuses that are used in a home or in an office are constructed tocommunicate with the help of electrical signals, which means that theneed for such an optical line to an apparatus is limited.

There is an increased need for fast communication with the help ofsignals that are led via optical fibres. It is therefore more and morecommon that optical fibres are drawn to a flat or to another part of abuilding. The apparatuses that communicate with the help of signals thatare sent via optical fibres normally require a conversion of the opticalsignals to electrical signals. This conversion may either take place inthe apparatus itself, which requires an optical line to the apparatus,or in a separate optoelectric converter. Such a converter also requiresits own current supply, which may be arranged in that the converter ispowered by a battery or in that a separate line for the current supplyis drawn to the converter. Furthermore, such a separate converterrequires space and is often in the way when cleaning or the like isperformed when it is positioned in a room, for example lying on thefloor. Such a separate converter may also easily be damaged if it liesunprotected. Faults may also occur along the optical transmission thatis the case in for example a flat, since the optical transmission isrelatively sensible to for example dirt or other influences.Furthermore, the light from the optical fibres may be harmful if forexample a child has access to the optical fibres and may direct thelight towards an eye.

A further problem with prior technology is that the supplier that hasthe responsibility for the optical connection to a flat or other part ofa building is not always responsible for damages on the connection thattakes place in the flat itself or within an office.

SUMMARY OF THE INVENTION

A purpose of the present invention is to achieve a contact device withwhich the above-described problems are avoided and that allows for awell functioning and simple use to a user of the contact device.

This purpose is achieved by a contact device comprising a carriermember, a receiving unit for receiving at least one optical fibre, acontrol circuit that includes a converter for converting opticalsignals, which are received via said at least one optical fibre, toelectrical signals and to convert electrical signals to optical signalsthat are to be transmitted via said at least one optical fibre, a firstcontact member connected to the control circuit such that electricalsignals from the converter are conducted to the first contact member andsuch that electrical signals from the first contact member are conductedto the converter, wherein the first contact member is designed such thata second contact member can be connected to the first contact member forconducting electrical signals from and to the first contact member,wherein said receiving unit, control circuit and first contact memberare fixed relative to the carrier member and wherein the contact deviceis designed to be fixable at a structural element in a room or otherpart of a building.

The receiving unit may for example consist of a sleeve, a so-calledferrule, in which the end of an optical fibre or fibre cable isarranged. The first contact member may for example be a female contact.An apparatus may thus according to this example be connected to thecontact device in that the apparatus is connected to an electric cablethat ends with a male contact that thus forms said second contactmember. The structural element may for example be a floor or a wall in apart of a building. Preferably, but not necessarily, at least twooptical fibres are connected to said receiving unit; one fibre maythereby be used to transmit signals from the contact device and anotherfibre to receive signals to the contact device. Since said controlcircuit with converter and said receiving unit form part of the contactdevice itself, an apparatus may be connected to the contact devicewithout any need for a separate converter between the apparatus and thecontact device. Furthermore, no optical fibre needs to be drawn from thecontact device to an apparatus or to a separate converter. It should benoted that the contact device in addition to the above mentionedcomponents, may of course also comprise further components. For example,the contact device may thus comprise further contact members in additionto the mentioned first contact member. The device may thus comprise twoor more contact members of the same kind as the first contact member.This makes it possible for for example several apparatuses that arepresent in a room to be connected to one and the same contact device.

According to a preferred embodiment of the contact device, it isdesigned to be fixable at least partly lowered relative to a mainsurface of said structural element, which main surface faces the room orthe part of the building, and wherein said receiving unit is fixed insuch a position relative to the carrier member that, when the contactdevice is fixed in position at said structural element, the receivingunit is suited to receive said at least one optical fibre when this atleast one optical fibre is led to the contact device via the structuralelement. According to this embodiment, the contact device may bearranged well protected. Since the optical fibre or fibres may be led tothe contact device via the structural element, also these fibres may bearranged well protected. It should be noted that the contact device doesnot necessarily have to be fixed lowered relative to said main surfaceof the structural element. Alternatively, the contact device may simplybe fixed at the structural element without being lowered therein. Thecontact device may in this case for example be designed with an outershell in the form of a box, such that this box may be fixed at said mainsurface of the structural element.

According to another embodiment of the contact device, the receivingunit is designed to receive said at least one optical fibre in adirection defined by the receiving unit, which direction defines astraight line, wherein the receiving unit is arranged at said carriermember such that, when the contact device is fixed in position at saidstructural element, the line forms an angle relative to said mainsurface that is less than 45 degrees. Preferably, said angle is lessthan 30 degrees and according to one embodiment essentially 0 degrees.This makes it possible that the optical fibre or fibres may be led tothe receiving unit when the fibres are essentially parallel to said mainsurface. This simplifies the connection of the optical fibres and meansthat undesired too sharp bends of the fibres are avoided.

According to still another embodiment of the contact device, itcomprises support members arranged to enable winding of excess of saidat least one optical fibre. This makes it possible for excess of opticalfibres that have been drawn to the structural element to easily be woundon these support members.

According to another embodiment of the contact device, it comprisesindication means connected to said control circuit for indicatingdifferent states of the contact device. A user may thereby observedifferent states of the contact device.

According to still another embodiment of the contact device, itcomprises a protective part that is suited to be fixed relative to saidcarrier member, such that, when the contact device is fixed at saidstructural element in a room or other part of a building and saidprotective part is fixed relative to said carrier member, at least saidcontrol circuit, said receiving unit and said at least one optical fibreare not within reach for a person that is in the room or the other partof a building without removing at least said protective part. This meansthat the risk of damaging these parts is avoided. The reliability of thedevice is thus improved.

According to still another embodiment of the contact device, itcomprises a holding member for holding a battery that may be used toprovide the control circuit with a supply voltage. Such a battery mayfor example have the purpose to secure that necessary supply voltage isapplied also in case a possible other source that provides the devicewith supply voltage does not work.

A further purpose of the present invention is to achieve a use of acontact device, by which use the above-described problems with priorknown devices are avoided.

This purpose is achieved in that the contact device according to any ofthe above-described embodiments is attached to said structural elementin a room in a flat or in another part of a building. The contactdevice, and thereby the parts that are included in the contact deviceare thereby fixed at the structural element, whereby is avoided that forexample converters or optical fibres are separately arranged in saidroom or other part of a building.

According to another preferred use, the structural element comprises arecess, wherein the contact device is arranged at least partly loweredin said recess. The contact device is thus arranged protected and is notin the way in said room or other part of the building. As has beenpointed out above, it is as an alternative also possible to fix thecontact device at the structural element without the contact devicebeing lowered in a recess.

According to another advantageous use the structural element is a wall.The contact device is thus fixed as a wall contact, which allows for aneasy access when a cable is to be connected to the contact device.

According to still an advantageous use, the contact device is connectedto a transformer that provides the contact device with a suitable supplyvoltage. It should be noted that the concept transformer according tothis document also comprises a so-called battery eliminator.

According to still an advantageous use, the transformer is connected toalternating current mains. The transformer may thereby be connected tothe common mains of for example 110 V or 220 V alternating current.

According to another advantageous use, the transformer is connected toan electrically conductive telephone line. A telephone line is oftendrawn to a room. Via this telephone line a suitable supply voltage maybe obtained. The transformer thereby transforms this supply voltage to avoltage suitable for the control circuit of the contact device, whichmay for example be 6V direct current voltage.

According to another advantageous use, also said transformer is fixed atthe structural element. It is thereby not necessary to have a separatetransformer that perhaps will be lying loose on the floor in the room orin the other part of a building.

According to a further advantageous use, the contact device is connectedto an electric wire that is drawn to the structural element and thatalso is connected to a supply unit that provides the contact device witha suitable supply voltage, wherein this supply unit is positioned at adistance from said structural element. The supply unit may for examplebe a transformer that is located in a basement of a house. Such atransformer may provide several contact devices in the house with asuitable supply voltage, which may be conducted to the contact devicesvia electrical lines. These electrical lines may possibly be drawntogether with the fibres. Alternatively, for example already existingelectrical telephone lines may be used.

According to still an advantageous use, the contact device is connectedto a supervisory system, with the help of which system the function ofthe contact device may be managed. A supplier that is responsible forinstalling fibres and contact devices may thus manage the function ofthe contact device, for example in order to analyse possible faults.

Other advantages of the present invention will become clear from thedescription below.

SHORT DESCRIPTION OF THE DRAWINGS

The present invention will now be explained and exemplified withreference to the annexed figures. It should be noted that the figuresonly schematically show examples of embodiments of the invention.

FIG. 1 shows a front view of a contact device according to theinvention.

FIG. 2 shows a cross-sectional view of the contact device according tothe section mark with A—A in FIG. 1.

FIG. 3 shows a view from behind of the contact device according to FIG.1.

FIG. 4 shows a view similar to that according to FIG. 1 but where thecontact device is provided with a protective part.

FIG. 5 shows a section similar to that of FIG. 2 but where the contactdevice is fixed at a wall.

FIG. 6 shows a similar section as FIG. 5, but where also a transformeris arranged at the wall.

FIG. 7 shows schematically the connection of a supervisory system to acontact device.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

An embodiment of the invention will next be described with reference toFIGS. 1-5.

The contact device thus comprises a carrier member 10. In the shownembodiment, the carrier member (see FIG. 2) has an upper part 10 a and alowered part 10 b. The carrier member 10, and thereby the contactdevice, is according to an advantageous use suitably fixed to astructural element 20 in a room 22 or in another part 22 of a building(see FIG. 5). Suitably, the structural element 20 is a wall. As is shownin FIG. 5, the contact device is suitably designed such that it may befixed at least partly lowered relative to a main surface 24 of the wall20, which main surface faces the room 22 or the part 22 of the building.As has been mentioned above, it is also possible that the contact deviceis fixed at for example a wall 20 without being lowered into the wall 20itself. The contact device may thereby comprise a box that simply may besecured by screws against a wall surface. The box may thereby bedesigned such that sensitive components are protected in the same.

A receiving unit 12 is fixed at the carrier member 10. This receivingunit 12 is designed such that an end of at least one optical fibre 14may be arranged therein (for the sake of clarity, the fibre is onlyshown in FIGS. 1 and 3). It should be noted that typically at least twofibres are arranged in the receiving unit 12. Suitably one fibre maythereby be used to transmit signals and one fibre may be used to receivesignals. Within the scope of the invention is however the possibilitythat only one fibre or more than two fibres are used. When in thedescription below, for the sake of simplicity, an optical fibre isdescribed, this should be interpreted such that it may in fact be morethan one fibre.

The receiving unit 12 may consist of a so-called ferrule. This may alsocomprise a detector for detecting incoming optical pulses and atransmitter, for example a laser, for transmitting optical pulses.Alternatively, such a detector and transmitter may be arranged separatefrom the receiving unit 12 and thus only be connected to the receivingunit 12. The receiving unit 12 is fixed such that it may receive theoptical fibre 14 when this at least one optical fibre 14 is led to thecontact device via the structural element 20, i.e. via the wall. Theoptical fibre 14 is thus suitably drawn to the room 22 without beingdrawn in the room 22 itself. It should however be noted that within thescope of the invention is the possibility that the optical fibre 14 isdrawn to the contact device in the room 22 itself.

This may for example be the case when the contact device is fixed at thewall 20 without being lowered into the wall 20. The optical fibre 14 maythereby be drawn to the contact device through the room 22 itself. Theoptical fibre or fibres 14 may thereby lie protected within a casing.Such a casing may for example already be arranged around the fibres orthe casing may consist of a tube that is arranged along for example thewall 20 or the floor in the room 22 for protecting the fibres.

The receiving unit 12 is designed to receive said optical fibre 14 in adirection 15 that is determined by in which position the receiving unit12 is fixed at the carrier member 10. This direction 15 thus defines astraight line. The receiving unit 12 is fixed at the carrier member 10such that, when the contact device is fixed in position at saidstuctural element 20, the line 15 forms an angle relative to said mainsurface 24 that is less than 45 degrees. Preferably, the angle is lessthan 30 degrees. It is also possible that the angle is essentially 0degrees. This means thus that said direction 15 is essentially parallelto the main surface 24 of the wall 22. This simplifies the fixation ofthe optical fibre 14 without it being subject to undesired bending.

The contact device also comprises support members 26 arranged to enablewinding (see FIG. 3) of excess of said optical fibre 14. Suitably, thecarrier member 10 comprises recesses or holes 28 for allowing theoptical fibre 14 to be introduced in through a part of the carriermember 10 to the receiving unit 12. The support members 26 are suitablyarranged such that the optical fibre 14 may be wound such that the woundfibre 14 is arranged essentially parallel to the main surface 24 of thewall 22 and such that the wound fibre 14 is well protected in a recess38 in the wall 20. In case the contact device is fixed at the wall 20without being lowered therein, the wound fibre 14 is suitably positionedprotected in a box that forms a protective casing of the contact device.Furthermore, the receiving unit 12 is preferably arranged at a distance,for example 1-5 cm, preferably 2-4 cm, from an imaginary central axis 30(see FIG. 2) through the contact device, which central axis 30 isperpendicular to the main surface 24 of the wall. The receiving unit 12is preferably arranged such that said line 15 is essentially tangentialor at least deviates with less than 30 degrees from the tangent, to animaginary circle that passes through the receiving unit 12, wherein thecircle is such that it lies in a plane that is perpendicular to saidcentral axis 30 and such that the centre of the circle coincides withsaid central axis 30. The optical fibre 14 may thereby be led from thesupport members 26 to the receiving unit 12 without being the subject ofundesired bendings.

The contact device also comprises a control circuit 16 (symbolicallymarked in FIG. 1) that includes a converter for converting opticalsignals, that are received via the optical fibre 14, to electricalsignals and for converting electrical signals to optical signals thatare to be transmitted via the optical fibre 14. The receiving unit 12 isconnected to the control circuit 16. As has been mentioned above, partsof the converter may possibly instead be included in the receiving unit12. It should be noted that such a control circuit 16 with optoelectricconverter is known per se and will therefore not be described moreclosely in this description.

The contact device also comprises a first contact member 18 that isconnected to the control circuit 16 such that electrical signals fromthe converter are conducted to the first contact member 18 and such thatelectrical signals from the first contact member 18 are conducted to theconverter. The first contact member 18 may for example be a femalecontact according to some suitable standard, for example according to RJor AUI. As has been mentioned above, it is also possible that thecontact device comprises more than one of said first contact members 18.The contact device may thus for example be provided with two or morefemale contacts such that several apparatuses in the room may beconnected to the contact device and thereby to the optical fibre orfibres that are drawn to the contact device.

The first contact member 18 is designed such that a second contactmember (not shown) may be connected to the first contact member 18 toconduct electrical signals from and to the first contact member 18. Thesecond contact member may thus be a male contact of the same standard asthe first contact member. The receiving unit 12, the control circuit 16and the first contact member 18 are fixed relative to the carrier member10.

The contact device also comprises indication means 32 that are connectedto said control circuit 16 for indicating different states of thecontact device. These indication means 32 may for example be lightemitting diodes. The indication means 32 may for example indicatewhether transmission or reception is going on and if current supply tothe control circuit 16 is the case.

The contact device also comprises a protective part 34 that is suited tobe fixed relative to said carrier member 10. When the contact device isfixed at for example a wall 20 and the protective part 34 is fixedrelative to the carrier member 10, the control circuit 16, the receivingunit 12 and the optical fibre 14 are not available to a person that isin the room 22. Such a person thus “sees” only the first contact member18 (or several such contact members if the contact device includes morethan one such contact member). The sensitive parts of the contact deviceare thus protected.

The contact device may also comprise a holding member 36 for holding abattery that may be used to provide the control circuit 16 with a supplyvoltage. Such a battery may for example be used as a back-up if othercurrent supply does not work. According to a non-shown alternative, theholding member 36 may be arranged at the contact device such that thebattery is available to a user that is in the room 22 without the userhaving to remove the protective part 34. A user may in this manner in asimple way exchange the battery.

As is shown in FIG. 5, the structural element 20, which may be a wall,is preferably provided with a recess 38, wherein the contact device isarranged at least partly lowered in the recess 38.

The control circuit 16 may suitably be of the kind that is powered witha low direct current voltage of for example 6V. In order to provide thecontact device with this supply voltage, it may be connected to atransformer 40 (see FIG. 6). The transformer 40 may also be what isoften called a battery eliminator. The transformer 40 may be fixed atthe structural element 20. As is shown in FIG. 6, the transformer 40 maybe arranged lowered into the structural element 20. Alternatively, thetransformer 40 may be arranged at a distance from the structural element20. The transformer 40 may of course also be fixed at the structuralelement 20 without being lowered therein. It is also possible that thetransformer is designed as a plug such that it may be directly pluggedinto an AC wall contact of a standard form. From such a transformer, awire may be drawn to the contact device for providing the contact devicewith supply voltage. Possibly, the contact device may thereby be fixednear or next to the AC wall contact.

The transformer 40 may connected to a cable 42 that forms part of the“common” alternating current mains (of for example 110 V or 220 V) andthat is already drawn to the structure element 20. Alternatively, thetransformer 40 may be provided with supply voltage via an electricallyconductive telephone line 44 that also may already have been drawn tothe structural element 20. Over such a telephone line 44 for example aDC-voltage of 40-50V may be provided.

According to an alternative, the contact device may be connected to anelectric line 46 (see FIG. 5) that is drawn to the structural element20. Such an electric line 46 may for example be drawn to the structuralelement 20 when the fibre 14 is drawn. The electric line 46 may alsoconsist of an already provided not used electric telephone line. Theelectric line 46 may in turn be connected to a supply unit, for examplein the form of a transformer, that provides the contact device with asuitable supply voltage and that is positioned at a distance from thestructural element 20. Such a supply unit may for example be arranged inthe basement of a house and provide many contact devices in the house orin the area with suitable supply voltage. The contact device mayaccording to one alternative also be connected to a battery thatfunctions as a back-up and that is positioned at a distance from thestructural element 20, for example in the basement or in another room ina house. If such a battery is the case, there is no need for a batteryback-up at the contact device itself.

As is schematically shown in FIG. 7, the contact device may be connectedto a supervisory system 50 (“management system”), with the help of whichsystem 50 the function of the contact device may be supervised. The oneresponsible for the system with fibres and contact devices may therebysupervise the function of these. For example, it may thereby besupervised if the supply voltage to the contact device functions, iftransmission and/or reception is the case, etc.

The supervisory system 50 may be connected to the control circuit 16 andthereby to the contact device in different manners that are symbolisedin FIG. 7. The connection may for example be via an already existingline 42 intended for AC-voltage, via an optical fibre 14, via anelectric telephone line 44 that already is drawn to the structuralelement 20, via another line 46 that provides the contact device withsupply voltage or via a separate line 52 drawn particularly in order toconstitute a connection to the supervisory system.

The invention is not limited to the described embodiments but may bevaried and modified within the scope of the claims.

1. A contact device, comprising: a carrier member; a receiving unit forreceiving at least one optical fiber; a control circuit that includes aconverter for converting optical signals, which are received via the atleast one optical fiber, to electrical signals and to convert electricalsignals to optical signals that are to be transmitted via the at leastone optical fiber; a first contact member connected to the controlcircuit such that electrical signals from the converter are conducted tothe first contact member and such that electrical signals from the firstcontact member are conducted to the converter, wherein the first contactmember is designed such that a second contact member can be connected tothe first contact member for conducting electrical signals from and tothe first contact member, wherein the receiving unit, the controlcircuit and first contact member are fixed relative to the carriermember and wherein the contact device is designed to be fixable at astructural element in a room or other part of a building, wherein thecontact device comprises a protective part that is suited to be fixedrelative to the carrier member, such that, when the contact device isfixed at the structural element in a room or other part of a buildingand the protective part is fixed relative to the carrier member, atleast the control circuit and the receiving unit are not within reachfor a person that is in the room or the other part of a building withoutremoving at least said protective part.
 2. The contact device accordingto claim 1, wherein the contact device is designed to be fixable atleast partly lowered relative to a main surface of the structuralelement, wherein the main surface faces the room or the part of thebuilding, and wherein the receiving unit is fixed in a position relativeto the carrier member such that, when the contact device is fixed inposition at the structural element, the receiving unit is suited toreceive the at least one optical fiber when the at least one opticalfiber is led to the contact device via the structural element.
 3. Thecontact device according to claim 2, wherein the receiving unit isdesigned to receive the at least one optical fiber in a directiondefined by the receiving unit, which direction defines a straight line,wherein the receiving unit is arranged at the carrier member such that,when the contact device is fixed in position at the structural element,the line forms an angle relative to the main surface that is less than45 degrees.
 4. The contact device according to claim 1, wherein thecontact device comprises support members arranged to enable winding ofexcess of the at least one optical fiber.
 5. The contact deviceaccording to claim 1, wherein the contact device comprises indicationmeans connected to the control circuit for indicating different statesof the contact device.
 6. The contact device according to claim 1,wherein the at least one optical fiber is not within reach of a personthat is in the room or the other part of a building when the protectivecover is fixed relative to the carrier member.
 7. The contact deviceaccording to claim 1, wherein the contact device comprises a holdingmember for holding a battery that may be used to provide the controlcircuit with a supply voltage.
 8. Use of a contact device according toclaim 1, wherein the contact device is attached to the structuralelement in a room in a flat or in another part of a building.
 9. The useaccording to claim 8, wherein the structural element comprises a recess,wherein the contact device is arranged at least partly lowered in therecess.
 10. The use according to claim 8, wherein the structural elementis a wall.
 11. The use according to claim 8, wherein the contact deviceis connected to a transformer that provides the contact device with asuitable supply voltage.
 12. The use according to claim 11, wherein thetransformer is connected to alternating current mains.
 13. The useaccording to claim 11, wherein the transformer is connected to anelectrically conductive telephone line.
 14. The use according to claim11, wherein the transformer is also fixed at the structural element. 15.The use according to claim 8, wherein the contact device is connected toan electric wire that is drawn to the structural element and that alsois connected to a supply unit that provides the contact device with asuitable supply voltage, wherein this supply unit is positioned at adistance from the structural element.
 16. The use according to claim 8,wherein the contact device is connected to a supervisory system, withthe help of which system the function of the contact device may bemanaged.